stuart



UNIT D STATES PATENT OFFICE.

ALBERT H. STUART, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO ABBIE ll.STUART, OF SAME PLACE.

MANDOLIN ATTACHMENT FOR PEANOS.

SPECIFICATION forming part of Letters Patent No. 578,048, dated March 2,1897.

Application filed May 13, 1896. Serial llo. 591,373. (No model.)

To all whom it may concern:

Be it known that I, ALBERT H. STUART, of Boston, in the county ofSuffolk and State of Massachusetts,have invented certain new and usefulImprovements in Mandolin Attachments for Pianos, of which the following,taken in connection with the accompanying drawings, is a specification.

My invention relates to mandolin attachments to pianos; and it consistsin certain novel features of construction, arrangement, and combinationof parts, which will be readily understood by reference to thedescription of the accompanying drawings, and to the claims heretoappended, and in which my invention is clearly pointed out.

Figure l of the drawings is asectional elevation of a portion of the endwall of a pianocase and my improved mandolin attachment drawn in fulllines, with one key and its ac tion shown in dotted lines; and Fig. 2 isa sectional elevation of the same parts, the cutting plane being on lineso a: on Fig. 1 and showing the piano key and action in dotted lines anda portion of the attachment in full lines.

In the drawings, A is the end wall of the piano-case, to which at theright of the series of keys is secured in a fixed position the block 13,having its upper surface substantially on a level with the upper surfaceof the keys, and said case has pivoted thereto at a the lever 0,provided with the headed stud l) and having secured to its free end oneend of the rail D, composed of the wooden core 0 and the sheet-metalcovering cl, the opposite end of which is secured to a similar lever orradius-arm pivoted to the opposite end wall of the case of theinstrument, but minus the stud Z).

E is a strut or push-rod having its upper end bifurcated and lined withleather 6 to engage the stud b and having its lower end rounded andcovered with leather f and arranged to rest upon the upper inclined faceof the wooden block F, secured to the end wall A of the case.

The strut E is guided in its back-and-forth motion, and the stroke ofits lower end is limited by a rectangular opening through the bar G, theinner surface of which is lined with felt, (not shown,) and its lowerend is connected by the link H with the operating rod or bar I, mountedupon the block B in a suitable guideway and provided at its front end.with the knob l, by which it may be moved toward the front or rear tovibrate the lever O, as may be desired.

The piano-strings g g are constructed and arranged in the usual manner,and therefore only small portions of them are shown here.

The rail D has secured to its rear side ascries of sheet-metal tongues7L, corresponding in number to the number of the hammers in the action,which project downward from said rail at an angle to the strings g g insuch a manner that when the rail is moved to the position indicated infull lines said tongues will be interposed between the hammers and thestrings to be acted upon thereby, but without touching either thestrings or the ham mers until the piano-key K is struck, when the hammerJ will strike the tongue h and force it into contact with the strings atthe rear of said hammer, which will produce the mandolin effect.

Between the wooden core 0 of the rail D and the tongues h is interposeda cushion i, of felt, of sufficient thickness to prevent any portion ofthe metal tongues 72, from coming in contact with the metal covering dof the rail 1).

The operation of my invention is as follows: The normal position of themandolin attachment is as indicated in dotted lines, but whenever itisdesired to produce the mandolin effect the operator draws the rod I tothe front until further movement of the lower end of the strut E isprevented by coming in contact with the front shoulder of the openingthrough the bar G, as indicated by the position shown in full lines inFig.1 when the rail D will be dropped into the position shown in fulllines, and the tongues It will be in positions to be struck by thehammers J and forced into contact with the strings, and as the hammersrecede said tongues are retracted by virtue of the elasticity of themetal of which they are formed.

V7 hat I claim as new, and desire to secure by Letters Patent of theUnited States, is-

1. I11 combination with the string and action of a piano, the rail Dsecured at each end to a lever or radius-arm O; the spring-metal tonguesh secured to said rail and projecting downward therefrom; the stud I)set in the lever O; the strut E having its upper end bifurcated; theblock F; link II; and operating-rod I, I, all constructed, arranged andoperating substantially as described.

2. In combination with the strings and action of apiano, the rail Dsecured at each end to a lever or radius-arm C; the studb set in a leveror radius-arm C; the strut E connected to said stud b; the block F forsupporting the strut E; means for moving the lower end of ALBERT ll.STUART.

\Vitnesses:

N. G. LOMBARD, L. C. GREENLEAF.

